a) Field of the Invention
The present invention is directed to an apparatus and associated method for the adjustment of the lamp in a microscope. The lamp is to be brought into the focal plane and oriented therein corresponding to the optical axis.
b) Description of the Related Art
In fluorescence microscopy and light microscopy, ultra-high pressure gas discharge lamps, for example, ultra-high pressure xenon or mercury gas discharge lamps, are used as excitation light sources and illumination light sources and are to be positioned in the beam path in a corresponding manner. In order to make better use of the light flux radiated by the lamp, there is an additional reflector mirror which projects the image of the light arc as exactly as possible in the plane of the light arc. There are essentially two disadvantages to the use of such lamps.
For one, the lamps that are used are subject to wear which expresses itself with increasing lighting hours in an increased electrode gap due to erosion. As a result, the intensity centroid of the illumination light moves out of the focus position in the optical axis so that the homogeneity of the illumination field worsens in addition. In order to compensate for this movement, a manual height adjustment is usually found in the illumination device.
The other disadvantage consists in that the gas discharge lamps that are used have large mechanical tolerances due to their method of manufacture. These tolerances express themselves, for example, in a different electrode spacing from the base or cap or from an axial run-out at which the glass body sits obliquely on the lamp foot.
For these reasons, an exact adjustment of the lamp, and possibly of the reflector mirror, with respect to the optical axis of the collector is necessary every time a lamp is changed.
The prior art discloses arrangements in which the lamp can be adjusted in the focal plane of the collector and reflector mirror can be adjusted in a plane parallel to the focal plane and along the optical axis.
Further, arrangements are known in which the reflector mirror is fixedly connected to the lamp housing so that only the lamp can still be adjusted in the focal plane of the collector and in direction of the optical axis of the collector. In both cases, it is possible, in addition, to focus the collector.
However, the arrangements mentioned above have the disadvantage that the sequence of adjustment steps to be carried out is very complex due to the many degrees of freedom and these adjustment steps require a certain basic knowledge of adjustment in order to achieve optimal adjustments.